World War 1

Assassination of Archduke Franz Ferdinand

Jun 28, 1914

The heir to the Austro-Hungarian throne Archduke Franz Ferdinand and his wife Sophie were assassinated in Sarajevo by Gavrilo Princip who was a Serbian nationalist. This event made tensions higher leading to World War 1.

Austria-Hungary Declares War on Serbia

Jul 28, 1914

Following the assassination, Austria-Hungary issued an ultimatum to Serbia. When Serbia’s response was deemed unsatisfactory Austria-Hungary declared war, setting off a chain reaction of alliances starting the war officially.

Germany Invades Belgium

Aug 4, 1914

Germany implemented the Schlieffen Plan, invading neutral Belgium to attack France. This act brought Britain into the war to defend Belgian neutrality.

First Battle of the Marne

Sep 6, 1914

Allied forces halted the German advance toward Paris in a decisive battle, leading to the establishment of trench warfare on the Western Front.

Introduction of Poison Gas in Warfare

Apr 22, 1915

Germany used chlorine gas at the Second Battle of Ypres, marking the first large-scale deployment of chemical weapons in warfare

Gallipoli Campaign

Apr 25, 1915

Allied forces launched an amphibious invasion of the Gallipoli Peninsula in an attempt to open a new front against the Ottoman Empire. The campaign ended in a costly defeat for the Allies.

Sinking of the RMS Lusitania

May 7, 1915

A German U-boat sank the British passenger liner Lusitania, killing 1,198 people, including 128 Americans. This escalated tensions with the United States.

Battle of Verdun

Feb 21, 1916

One of the longest and bloodiest battles of the war, where French and German forces fought over a small area, resulting in massive casualties. War lasted for 303 days.

Battle of Jutland

May 31, 1916

The largest naval battle of World War I between the British Royal Navy and the Imperial German Navy. While tactically inconclusive, it reinforced British naval dominance and forced Germany to rely more heavily on submarine warfare.

Battle of the Somme

Jul 1, 1916

Marked by extensive trench warfare, the battle was one of the costliest in terms of lives lost and introduced the use of tanks on the battlefield.

Zimmermann Telegram

Jan 17, 1917

A secret German proposal urging Mexico to join the war against the U.S. was intercepted and made public, inflaming American opinion.

United States Enters the War

Apr 6, 1917

The U.S. declared war on Germany after repeated U-boat attacks and the Zimmermann Telegram, significantly bolstering the Allied powers.

Russian Revolution and Withdrawal

Mar 3, 1918

The Bolsheviks seized power in Russia, leading to the country’s withdrawal from the war through the Treaty of Brest-Litovsk with Germany. The revolution took place on November of 1917 but the treaty was signed in March of 1918.

German Spring Offensive

Mar 21, 1918

Germany launched a series of offensives to break the stalemate before American forces arrived in full strength, but they ultimately failed.

Second Battle of the Marne

Jul 15, 1918

The Allied forces, bolstered by U.S. troops, repelled the last major German offensive, marking the beginning of Germany’s retreat.

Armistice Day

Nov 11, 1918

Germany signed an armistice agreement with the Allies, ending the fighting on the Western Front at 11 a.m.

Signing of the Treaty of Versailles

Jun 28, 1919

he Treaty of Versailles officially ended the war, imposing harsh penalties on Germany and redrawing the map of Europe.